22.Factors That Affect Fertility Section 4.3 Sperm Shape: Does It Affect Fertility?
"Patient Fact Sheet: Sperm Shape (Morphology): Does It Affect Fertility?"
Copyright 2008 by the American Society for Reproductive Medicine. All rights reserved. No part of this presentation may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage and retrieval system without permission in writing from the American Society for Reproductive Medicine, 1209 Montgomery Highway, Birmingham, AL 35216.
How do doctors decide if a man might have a fertility problem? For many years, experts have focused on s.e.m.e.n a.n.a.lysis, but research studies show that the number of sperm (count) and the movement of sperm (motility) do not always predict fertility very well by themselves. It may also be useful to look at the shape of the sperm (morphology), which is also one of the important parts of the s.e.m.e.n evaluation.
An updated way of determining sperm shape is called the Kruger"s strict morphology method. Kruger morphology is a useful system that helps doctors determine if a sperm is normally shaped or not. It was originally used to predict the success of in vitro fertilization (IVF), a fertility treatment in which the sperm are mixed with the woman"s egg in a laboratory. More recently, it has been used to tell if intracytoplasmic sperm injection (ICSI) is a necessary treatment. ICSI is a procedure that helps a sperm fertilize an egg by injecting a single sperm directly into the center of the egg.
Even though it is used for these purposes, not all physicians and scientists are sure that strict morphology method alone predicts success with IVF or whether it indicates the need for ICSI.
Characteristics of normal sperm. A normal sperm has: * a smooth, oval shaped head that is 56 micrometers long and 2.53.5 micrometers around (less than the size of a needle point); * a well defined cap (acrosome) that covers 40% to 70% of the sperm head; * no visible defect of neck, midpiece, or tail; 23.Pregnancy and Birth Sourcebook, Third Edition * no fluid droplets in the sperm head that are bigger than one-half of the sperm head size.
Intercourse versus artificial insemination. For patients with fertility problems, sperm morphology may have an effect on your ability to achieve a pregnancy. If the strict sperm morphology is more than 4%, there may be little difference in success whether timed intercourse or artificial insemination is utilized.
In vitro fertilization. A successful pregnancy using IVF depends on many of factors: how many eggs are fertilized, whether the fertilized eggs grow into embryos, and whether the embryo implants in the woman"s uterus. When strict morphology is 4% or less, eggs may have a better chance of fertilization with the use of ICSI.
Frequently Asked Questions If an abnormally shaped sperm fertilizes the egg, does that mean that my child will have genetic abnormalities?
There"s no scientific link between the shape of a sperm and its chromosomal content. Once the sperm penetrates the egg, fertilization has a good chance of taking place. However, there may be some male offspring who will inherit the same type of morphology abnormalities. Whether routine investigation of Y-chromosome abnormalities should be initiated when low morphology is noted is controversial.
Are there any substances that I can reduce or eliminate exposure to (e.g., alcohol, tobacco, caffeine) in order to im- prove the shape of my sperm?
Studies haven"t shown a clear link between abnormal sperm shape and these factors, but it"s a good idea to try to eliminate use of tobacco and recreational drugs and limit your consumption of alcohol. These substances reduce sperm production and function in several ways.
They may hurt sperm DNA (material that carries your genes) quality. Studies have not shown a clear link between caffeine consumption and changes in sperm shape.
Are there any dietary supplements or vitamins that I can take to improve morphology?
Dietary supplements or vitamins have not been clearly shown to improve sperm morphology. Some specialists do recommend that you 24 Factors That Affect Fertility take a daily multivitamin to improve a number of body functions, including reproductive health.
Section 4.4 Paternal Exposures to Toxins "Paternal Exposures and Pregnancy," 2002 Organization of Teratology Information Services (OTIS). Reprinted with permission. Member programs of OTIS are located throughout the U.S. and Canada. To find the Teratogen Information Service in your area, call OTIS toll-free at 866-626-OTIS (866-626-6847), or visit www.otispregnancy.org. Reviewed by David A. Cooke, MD, FACP, April 29, 2009.
This text talks about the risks that paternal exposures can have during pregnancy. With each pregnancy, all women have a 3% to 5% chance of having a baby with a birth defect. This information should not take the place of medical care and advice from your health care provider.
What is a paternal exposure?
A paternal exposure is anything the father of the baby is exposed to before conception or during his partner"s pregnancy. Examples include recreational drugs, alcohol, cigarette smoking, chemotherapy or radiation treatments, environmental or occupational exposures, and prescription or over-the-counter medications.
Do paternal exposures cause any problems related to preg- nancy?
Yes. Certain exposures may affect a man"s ability to father a child by changing the production, size, shape, or performance of sperm. Such changes may cause infertility, delay in getting his partner pregnant, or early pregnancy loss. Data from animal and human studies suggest that paternal exposures may cause genetic changes in sperm which may cause an embryo to fail to develop or cause an increased risk for childhood cancers in an exposed man"s children.
25.Pregnancy and Birth Sourcebook, Third Edition Do paternal exposures cause birth defects?
Agents that may cause birth defects do not reach the developing fetus through the father as they do from the pregnant woman. Substances that a father is exposed to may be found in small amounts in the s.e.m.e.n, but there is no evidence that these small amounts interfere with normal fetal development. Currently, there is no evidence that paternal exposures increase the risk of birth defects. However, further study is needed in this area.
Can recreational drugs, if used by the father, affect my pregnancy?
These substances may be found in the s.e.m.e.n. Recreational drug use may affect sperm quality or provide limited direct exposure to the developing fetus. However, there is no clear evidence that birth defects may result from the use of these substances by the father.
Can alcohol use by the father affect my chances of getting pregnant or affect the baby during pregnancy?
Heavy alcohol use in males may affect sperm formation and function, or may cause impotence. Whether a father"s alcohol use increases the risks for birth defects is still being investigated. A recent study suggested that paternal alcohol use may be a.s.sociated with an increased risk for certain rare heart defects in newborns. More information is needed in this area before a conclusion can be made.
What if the father of the baby smokes cigarettes?
Paternal smoking has been a.s.sociated with small reductions in sperm quality, but there have been no reports of reduced fertility due to smoking in men. A small a.s.sociation between adverse pregnancy effects and paternal smoking, and a slight increase in certain types of cancer in offspring of smoking fathers has been seen. One study on a small number of babies born with rare heart defects found an a.s.sociation with paternal smoking. Additional studies on the effects of paternal smoking on pregnancy outcome are needed.
Can chemotherapy or radiation for cancer treatments given to the father affect my pregnancy?
Sperm production is frequently affected during cancer treatment.
Sometimes, sperm production may return to normal after certain chemotherapy or radiation treatments, but it is not guaranteed.
26.Factors That Affect Fertility Men who are facing cancer treatment may wish to consider sperm banking prior to starting treatment. It is recommended that men undergoing chemotherapy wait for at least three months after the end of treatment before attempting to father a child. Certain chemotherapy treatments have been shown to increase the chance of having a fetus with more or less than the normal number of chromosomes.
Damage to the structure of chromosomes in sperm of cancer patients may also occur. It is believed that most of the damage is not permanent, but some studies have detected higher than normal levels of abnormal sperm years after the end of chemotherapy. At this time, there are no data demonstrating an increase in birth defects in the children of cancer patients.
Can the father"s workplace exposures affect my pregnancy?
According to the National Inst.i.tute of Occupational Safety and Health (NIOSH), a number of workplace substances including lead, organic solvents, pesticides, and radiation have been identified as reproductive hazards to men. Some studies in humans suggest that such exposures may be a.s.sociated with decreased sperm production, increased sperm abnormalities, decreased fertility, and an increased risk of miscarriage in the wives of these workers.
In addition, men exposed to heavy metals, pesticides, and other chemicals in the workplace may carry very small amounts of these agents on their clothes and shoes into the home. This may cause direct exposure of their partner prior to conception or during pregnancy. However, no data are available at this time regarding any increases in birth defects due to such exposures. Further studies are needed in these areas.
Can prescription or over-the-counter medications taken by the father affect my pregnancy?
Paternal exposure to medications prescribed for conditions like high blood pressure or high cholesterol have not been a.s.sociated with an increased risk of birth defects in the developing fetus. Likewise, over-the-counter medications to treat other conditions have not been a.s.sociated with an increased risk of birth defects. However, it is important to discuss any concerns you may have with your physician.
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27.Pregnancy and Birth Sourcebook, Third Edition Cohen FL. 1986. Paternal contribution to birth defects. Nurs Clin Nurs Clin North Amer North Amer 21:4964. 21:4964.
Colie CF 1993. Male mediated teratogenesis. Reprod Toxicol Reprod Toxicol 7:39. 7:39.
Correa-Villasenor A, et al. 1993. Paternal exposures and cardiovascular malformations. The Baltimore-Washington Infant Study Group.
J Expo a.n.a.l Environ Epidemiol Suppl 1:173185. 1:173185.
Generoso WM, et al. 1990. Concentration-response curves for ethyl-ene oxide-induced heritable translocations and dominant lethal mutations. Environ Mol Mutagen Environ Mol Mutagen 16:126131. 16:126131.
Generoso WM, et al. 1995. Dominant lethal and heritable translocation tests with chlorambucil and melphalan in male mice. Mutat Res Mutat Res 345:167180. 345:167180.
Generoso WM, et al. 1975. 6-Mercaptopurine: an inducer of cytoge-netic and dominant lethal effects in premeiotic and early meiotic germ cells of male mice. Mutat Res Mutat Res 28:437447. 28:437447.
Hunt PA. 1987. Ethanol-induced aneuploidy in male germ cells of the mouse. Cytogenet Cell Genet Cytogenet Cell Genet 44(1):710. 44(1):710.
Jensen BK, e al. 1991. The negligible availability of retinoids with multiple and excessive topical application of isotretinoin 0.05% gel (Isotrex) in patients with acne vulgaris. J Am Acad Dermatol J Am Acad Dermatol 24:425 24:425 428.
Ji BT, Shu XO, Linet MS, Zheng W, Wacholder S, Gao YT, Ying DM, Jin F (1997) Paternal cigarette smoking and the risk of childhood cancer among offspring of nonsmoking mothers. J Natl Cancer Inst J Natl Cancer Inst 89:238244. 89:238244.
Obe G and Anderson D. 1987. International Commission for Protection against Environmental Mutagens and Carcinogens. ICPEMC Working Paper No. 15/1. Genetic effects of ethanol. Mutat Res Mutat Res 186(3): 177200. 186(3): 177200.
Pearn JH. 1983. Teratogens and the male. Med J of Austr Med J of Austr 2:1620. 2:1620.
Sallmen M, et al. 1998, Time to pregnancy among the wives of men exposed to organic solvents. Occup Environ Med Occup Environ Med 55:2430. 55:2430.
Sallmen M, et al. 2000 Paternal exposure to lead and infertility.
Epidemiol 11(2):148152. 11(2):148152.
28.Factors That Affect Fertility Sallmen M, et al. 1998. Time to pregnancy among the wives of men exposed to organic solvents. Occup Environ Med. Occup Environ Med. 55(1):2430. 55(1):2430.
Savitz DA, et al. 1991. Influence of paternal age, smoking, and alcohol consumption on congenital anomalies. Teratology Teratology 44:429440. 44:429440.
Shelby MD, et al. 1986. Dominant lethal effects of acrylamide in male mice. Mutat Res Mutat Res 173:3540. 173:3540.
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Taskinen H, et. al. 1989. Spontaneous abortions and congenital malformations among the wives of men occupationally exposed to organic solvents. Scand J Work Environ Health Scand J Work Environ Health 15:34552. 15:34552.
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29.
Chapter 5.
Trying to Conceive Chapter Contents.Section 5.1-Tips for Trying to Conceive ..................................... 32 Section 5.2-Do s.e.xual Positions Affect Conception? ................ 41 Section 5.3-Using Ovulation Predictor Kits .............................. 42 31.Pregnancy and Birth Sourcebook, Third Edition Section 5.1 Tips for Trying to Conceive From "Trying to Conceive," by the Office of Women"s Health (www.womenshealth.gov), part of the U.S. Department of Health and Human Services, April 2006.
Fertility Awareness The Menstrual Cycle Being aware of your menstrual cycle and the changes in your body that happen during this time can be key to helping you plan a pregnancy, or avoid pregnancy. During the menstrual cycle (a total average of 28 days), there are two parts: before ovulation and after ovulation.
* Day 1 starts with the first day of your period.
* Usually by Day 7, a woman"s eggs start to prepare to be fertilized by sperm.
* Between Day 7 and 11, the lining of the uterus (womb) starts to thicken, waiting for a fertilized egg to implant there.
* Around Day 14 (in a 28-day cycle), hormones cause the egg that is most ripe to be released, a process called ovulation. The egg travels down the fallopian tube towards the uterus. If a sperm unites with the egg here, the egg will attach to the lining of the uterus, and pregnancy occurs.
* If the egg is not fertilized, it will break apart.
* Around Day 25 when hormone levels drop, it will be shed from the body with the lining of the uterus as a menstrual period.
The first part of the menstrual cycle is different in every woman, and even can be different from month-to-month in the same woman, varying from 13 to 20 days long. This is the most important part of the cycle to learn about, since this is when ovulation and pregnancy 32 Trying to Conceive can occur. After ovulation, every woman (unless she has a health problem that affects her periods) will have a period within 14 to 16 days.
Charting Your Fertility Pattern Knowing when you"re most fertile will help you plan or prevent pregnancy. There are three ways you can keep track of your fertile times. They are: Basal body temperature method: Basal body temperature is your temperature at rest as soon as you awake in the morning. A woman"s basal body temperature rises slightly with ovulation. So by recording this temperature daily for several months you"ll be able to predict your most fertile days. Basal body temperature is your temperature at rest as soon as you awake in the morning. A woman"s basal body temperature rises slightly with ovulation. So by recording this temperature daily for several months you"ll be able to predict your most fertile days.
Basal body temperature differs slightly from woman to woman.
Anywhere from 96 to 98 degrees orally is average before ovulation.
After ovulation most women have an oral temperature between 97 and 99 degrees. The rise in temperature can be a sudden jump or a gradual climb over a few days.
Usually a woman"s basal body temperature rises by only 0.4 to 0.8 degrees Fahrenheit. To detect this tiny change, women must use a basal body thermometer. These thermometers are very sensitive. Most pharmacies sell them for around $10. You then record your temperature on a special chart.
The rise in temperature doesn"t show exactly when the egg is released. But almost all women have ovulated within three days after their temperatures spike. Body temperature stays at the higher level until your period starts.
You are most fertile and most likely to get pregnant: * two to three days before your temperature hits the highest point (ovulation), and * 12 to 24 hours after ovulation.
A man"s sperm can live for up to three days in a woman"s body. The sperm can fertilize an egg at any point during that time. So if you have unprotected s.e.x a few days before ovulation there is a chance of becoming pregnant.
Many things can affect basal body temperature. To get the most useful chart you should take your temperature every morning at about the same time. Things that can alter your temperature include: * drinking alcohol the night before; 33.Pregnancy and Birth Sourcebook, Third Edition * smoking cigarettes the night before; * getting a poor night"s sleep; * having a fever; * doing anything in the morning before you take your temperature-including going to the bathroom and talking on the phone.
Calendar method: This involves keeping a written record of each menstrual cycle on a calendar. The first day of your period is Day 1. This involves keeping a written record of each menstrual cycle on a calendar. The first day of your period is Day 1.
Circle Day 1 on the calendar. Do this for eight to 12 months so you know how many days are in your cycle. The length of your cycle may vary from month to month. So write down the total number of days it lasts each time. To find out the first day when you are most fertile, check your list for the cycle with the fewest days. Then subtract 18 from that number. Take this new number and count ahead that many days on the calendar. Draw an X through this date. The X marks the first day you"re likely to be fertile. To find out the last day when you are fertile, subtract 11 days from your longest cycle and draw an X through this date. This method always should be used with other fertility awareness methods, especially if your cycles are not always the same lengths.
Cervical mucus method (also known as the ovulation method): This involves being aware of the changes in your cervical mucus throughout the month. The hormones that control the menstrual cycle also change the kind and amount of mucus you have before and during ovulation. Right after your period, there are usually few days when there is no mucus present or "dry days." As the egg starts to mature, mucus increases in the v.a.g.i.n.a, appears at the v.a.g.i.n.al opening, and is white or yellow and cloudy and sticky. The greatest amount of mucus appears just before ovulation. During these "wet days" it becomes clear and slippery, like raw egg whites. Sometimes it can be stretched apart. (also known as the ovulation method): This involves being aware of the changes in your cervical mucus throughout the month. The hormones that control the menstrual cycle also change the kind and amount of mucus you have before and during ovulation. Right after your period, there are usually few days when there is no mucus present or "dry days." As the egg starts to mature, mucus increases in the v.a.g.i.n.a, appears at the v.a.g.i.n.al opening, and is white or yellow and cloudy and sticky. The greatest amount of mucus appears just before ovulation. During these "wet days" it becomes clear and slippery, like raw egg whites. Sometimes it can be stretched apart.
This is when you are most fertile. About four days after the wet days begin the mucus changes again. There will be much less and it becomes sticky and cloudy. You might have a few more dry days before your period returns. Describe changes in your mucus on a calendar. Label the days, "Sticky," "Dry," or "Wet." You are most fertile at the first sign of wetness after your period or a day or two before wetness begins. This method is less reliable for some women. Women who are breastfeeding, taking hormonal contraceptives (like the pill), using feminine hygiene products, have vaginitis or s.e.xually transmitted diseases (STDs), or have had surgery on the cervix should not rely on this method.
34.Trying to Conceive To most accurately track your fertility, use a combination of all three methods. This is called the symptothermal method.
Infertility It is not uncommon to have trouble becoming pregnant or to experience infertility. Infertility is defined as not being able to become pregnant, despite trying for one year, in women under age 35, or after six months in women 35 and over. Pregnancy is the result of a chain of events. As described in the Fertility Awareness section, a woman must release an egg from one of her ovaries (ovulation). The egg must travel through a fallopian tube toward her uterus. A man"s sperm must join with (fertilize) the egg along the way. The fertilized egg must then become attached to the inside of the uterus. While this may seem simple, in fact many things can happen to prevent pregnancy.
Reasons for Infertility Age There are many different reasons why a couple might have infertility. One is age-related. Women today are often delaying having children until later in life, when they are in their 30s and 40s. A couple of things add to this trend. Birth control is easy to obtain and use, more women are in the work force, women are marrying at an older age, the divorce rate remains high, and married couples are delaying pregnancy until they are more financially secure. But the older you are, the harder it is to become pregnant. Women generally have some decrease in fertility starting in their early 30s. And while many women in their 30s and 40s have no problems getting pregnant, fertility especially declines after age 35.
As a woman ages, there are normal changes that occur in her ovaries and eggs. All women are born with over a million eggs in their ovaries (all the eggs that they will ever have), but only have about 300,000 left by p.u.b.erty. Then of these, only about 300 eggs will be ovulated during the reproductive years. Even though menstrual cycles continue to be regular in a woman"s 30s and 40s, the eggs that ovulate each month are of poorer quality than those from her 20s. It is harder to get pregnant when the eggs are poorer in quality.
Ovarian reserve is the number and quality of eggs in your ovaries and how well the ovarian follicles respond to hormones in your body.
As you approach menopause, your ovaries don"t respond as well to 35 Pregnancy and Birth Sourcebook, Third Edition your hormones, and in time they may not release an egg each month.
A reduced ovarian reserve is natural as a woman ages, but young women might have reduced ovarian reserves due to smoking, a prior surgery on their ovaries, or a family history of early menopause. Also, as a woman and her eggs age, if she becomes pregnant, there is a greater chance of having genetic problems, such as having a baby with Down syndrome. Embryos formed from eggs in older women also are less likely to fully develop, a main reason for miscarriage (early pregnancy loss).
Health Problems Couples also can have fertility problems because of health problems, in either the woman or the man. Common problems with a woman"s reproductive organs, like uterine fibroids, endometriosis, and pelvic inflammatory disease can worsen with age and also affect fertility. These conditions might cause the fallopian tubes to be blocked, so the egg can"t travel through the tubes into the uterus.
Some people also have diseases or conditions that affect their hormone levels, which can cause infertility in women and impotence and infertility in men. Polycystic ovarian syndrome (PCOS) is one such hormonal condition that affects many women, and is the most common cause of anovulation, or when a woman rarely or never ovulates.