Female Infertility

How conception works

Pregnancy needs an egg to be released (ovulation), sperm to reach the egg in the fallopian tube, fertilization, and the embryo to travel to and implant in a healthy uterus. Problems at any step can cause infertility. Healthy couples under 30 have about a 20% chance of conceiving each cycle, and most conceive within a year.

Causes of female infertility

Ovulation disorders

• Polycystic ovary syndrome (PCOS): the most common cause, with irregular periods, excess hair growth, acne and often weight gain.
• Hypothalamic amenorrhea: low body weight, intense exercise or stress switches off ovulation.
• Thyroid problems (hypothyroidism) and high prolactin (hyperprolactinemia).
• Premature ovarian insufficiency: loss of ovarian function before 40.

Tubal damage

Pelvic inflammatory disease, usually from chlamydia or gonorrhea, can scar or block the fallopian tubes. Previous ectopic pregnancy, appendicitis with rupture, pelvic surgery and endometriosis also damage tubes.

Endometriosis

Endometriosis affects fertility through scarring, distorted anatomy, inflammation and effects on egg quality.

Uterine factors

Fibroids that distort the uterine cavity, endometrial polyps, scar tissue (Asherman syndrome) and a uterine septum can interfere with implantation.

Age

Egg number and quality decline with age, especially after 35 and steeply after 40. By 40, the chance of conceiving per cycle is about 5%, and miscarriage rates rise.

Lifestyle factors

Smoking, heavy alcohol use, obesity, being underweight and some medicines can reduce fertility.

Signs of infertility in women

Many women have no symptoms other than not getting pregnant. Possible clues:

• irregular cycles (shorter than 21 or longer than 35 days) or no periods
• very heavy or painful periods
• pelvic pain or pain during sex
• signs of hormonal imbalance: excess hair, acne, milky nipple discharge

Fertility evaluation

Both partners are assessed together.

1. History and examination: cycles, pregnancies, infections, surgery, medicines, lifestyle.
2. Confirming ovulation: a mid-luteal progesterone blood test (about 7 days before the expected period), or ovulation predictor kits.
3. Hormone tests: thyroid function, prolactin, and others if cycles are irregular.
4. Ovarian reserve: anti-Müllerian hormone (AMH), day 3 FSH and estradiol, and antral follicle count on ultrasound. These predict response to treatment more than natural fertility.
5. Tubal patency: hysterosalpingogram (HSG), an X-ray with dye, or saline-and-air sonography.
6. Uterine evaluation: transvaginal ultrasound, saline sonohysterography or hysteroscopy.
7. Laparoscopy: keyhole surgery if endometriosis or pelvic adhesions are suspected.
8. Semen analysis for the male partner. See male factor infertility.

Treatment options

• Lifestyle changes: reaching a healthier weight, stopping smoking, limiting alcohol and taking folic acid.
• Ovulation induction: letrozole (first-line for PCOS) or clomiphene, with monitoring. Injectable gonadotropins are used if these fail.
• Treating hormonal causes: thyroid hormone, dopamine agonists for high prolactin.
• Surgery: removing polyps, fibroids distorting the cavity or a uterine septum; treating endometriosis; occasionally repairing tubes.
• Intrauterine insemination (IUI): prepared sperm placed in the uterus around ovulation, often with ovulation medicines.
• In vitro fertilization (IVF): eggs collected after ovarian stimulation, fertilized in the lab, and embryos transferred to the uterus. Used for blocked tubes, severe male factor, advanced age, endometriosis and when other treatments fail.
• Donor eggs for premature ovarian insufficiency or very low ovarian reserve.
• Egg freezing to preserve fertility for later.

Treatment risks include multiple pregnancy and ovarian hyperstimulation syndrome, which careful monitoring reduces.

Emotional impact

Infertility can cause grief, stress, relationship strain and depression. Counseling and support groups help, and many fertility clinics offer psychological support.

Frequently asked questions

What are the most common causes of female infertility?

The most common causes are ovulation problems (especially PCOS), blocked or damaged fallopian tubes, endometriosis, uterine problems such as fibroids or polyps, and declining egg number and quality with age. In some couples no cause is found.

When should I see a doctor about infertility?

See a doctor if you have not conceived after 12 months of trying under age 35, or after 6 months at 35 to 39. Seek help immediately if you are 40 or older, or have irregular periods, known endometriosis, prior pelvic infection or previous cancer treatment.

What tests are done for female infertility?

Tests include blood tests to confirm ovulation and check hormones, ovarian reserve tests such as AMH, a transvaginal ultrasound, an X-ray dye test (HSG) of the fallopian tubes, and sometimes laparoscopy or hysteroscopy. The male partner also has a semen analysis.

Can female infertility be treated?

Yes, in most cases. Options include medicines to trigger ovulation, surgery for structural problems or endometriosis, intrauterine insemination, and IVF. Success depends on the cause and especially on age.