Secondary infertility is defined as the inability to become pregnant, or to carry a pregnancy to term, following the birth of one or more biological children. The birth of the first child does not involve any assisted reproductive technologies or fertility medications.
Specific causes of secondary infertility
Maternal Age: The mother’s age is one of the most common reasons for secondary infertility. The natural decline in ovarian function is the single most important factor in fertility. It is important to realize that women are born with all of the eggs they will ever have. As a woman ages, the egg quality decreases, and the chances of miscarriage increases. Men, however, produce new sperm every day.
Pelvic/tubal factors: Sexually transmitted disease, endometriosis and a history of ruptured appendix can lead to pelvic adhesions that interfere with the ability of the egg to be picked up by the fallopian tubes. For example, if there were complications during a prior delivery and a woman developed a uterine infection, or if she underwent a difficult pelvic surgery, she may be at risk for a condition known as Asherman’s syndrome (intrauterine adhesions as a result of scarring after uterine surgery), or adhesions around the fallopian tubes which prevent the tube from capturing the ovum during ovulation.
Male factor: Changes in sperm quality or quantity may occur due to changes in health or beginning certain new medications. I continue to be amazed, for example, at the number of couples I see in which the male was given testosterone supplementation by a family practice doctor or internist. The effect of such treatment decreases male sperm production dramatically and can often take a year to get back to normal after stopping the medication.
Life style issues: Factors such as weight can have an impact on the ability to conceive. Excessive weight contributes to ovulatory disorders. As a woman’s weight increases, insulin resistance may increase as well, leading to elevated production of male hormones, such as testosterone, which affect ovulation. For men, excessive weight can increase male estrogen levels which can negatively affect sperm production. Cigarette smoking can also impact egg quality and increase complications during a pregnancy.
Fertility medications such as clomid or injectible gonadotropins are used to increase the number of eggs available for fertilization, either naturally or with intrauterine insemination, or in vitro fertilization. The use of IVF allows us to bypass pelvic/tubal problems, and also increases fertilization in cases of severe sperm related abnormalities. When the issue is diminished ovarian function, egg donation is an option for those with secondary infertility.
Current treatment has improved dramatically, thus encouraging couples to seek help in overcoming fertility challenges. For example, the pregnancy rates for couples using assisted reproductive technology (ART) now exceed the monthly fertility rate for couples without fertility problems.