A woman's weight can have a great impact on her fertility, as well as her health during and after pregnancy. Her child's health may also be affected. One tool for assessing whether someone is at a healthy weight is the BMI, or body mass index. To discover the BMI, divide the person's weight in pounds by her height in inches. This can be done manually, or it can be ascertained by using a BMI calculator, available in doctors offices and many health websites.
Identification
For women trying to become pregnant, a BMI of greater than 18.5, but less than 25 is ideal, according to Fitpregnancy.com. Women whose BMI falls below or above these guidelines are at an increased risk of infertility and face more risks to the baby's health if they do become pregnant.
Significance for Infertility
High or low weight can affect ovulatory function, as well as insulin resistance. This can lead to fertility problems. Even with fertility treatments, women who are very over or underweight are less likely to get pregnant, reports Womens-health.jwatch.org.
During Pregnancy
Once pregnant, women who have a high BMI, especially a BMI over 30, face increased risk. Overweight women have a higher chance of miscarriage and stillbirth. They are also more likely to develop gestational diabetes or gestational hypertension, as well as preeclampsia, a blood pressure condition that can lead to a baby needing to be delivered early. The babies of women with high BMIs also can face problems, such as neural tube defects, prematurity and being more likely to be overweight in childhood themselves, according to The American Congress of Obstetricians and Gynecologists. It is also more difficult to spot fetal abnormalities during ultrasound on women who have high BMIs, reports Womenshealth.gov.
Childbirth
There are also more risks for a woman with a high BMI during delivery. The chances of having a Cesarean section increases as a woman's BMI increases. If she does have a c-section, there is a greater likelihood of having complications afterwards, such as wound infection and too much blood loss from surgery.
Considerations
If possible, a woman should achieve a healthy weight before trying to conceive. It is especially important for women with high or very low BMIs to receive adequate prenatal care, and to gain weight in accordance with the recommended guidelines. For most women, a weight gain of 25 to 35 pounds during pregnancy is average, but a woman who is over or underweight should discuss with her doctor how much weight gain is good for her.
