Getting pregnant isn't easy, even under the best of circumstances. In any given month, only 15 to 20 percent of couples under age 35 actively trying to get pregnant achieve their goal. Over a one year period, 85 percent will get pregnant, and 95 percent will get pregnant within two years of trying, Women's Health UK states. The number of things that can go wrong in the process of human reproduction are so staggering it's a miracle anyone manages to reproduce.
Female Issues
In some countries, even today, the inability to provide offspring is automatically assumed to be the woman's fault. While there are certainly a number of workable parts to the female reproductive system, fertility issues solely related to the female occur in only 50 percent of cases, according to the Mayo Clinic. Problems that can interfere with female fertility include hormonal problems, structural problems with the cervix, uterus, ovary or fallopian tubes, and ovary problems.
Abnormalities in the hormone levels responsible for developing a mature egg each month result in anovulation, which means lack of ovulation, or irregular ovulation. Advanced age and medical conditions such as polycystic ovarian syndrome or Turner syndrome can lead to anovulation. If no egg is produced, pregnancy is impossible. Endometriosis, implantation of endometrial tissue outside the uterus, can surround the ovary and make egg release impossible.
Women are born with all the eggs they'll ever have, and the eggs age as they do. Increased maternal age increases the number of chromosomally abnormal eggs, which may not fertilize or may cause early miscarriage. One third of women over age 35 have infertility issues, the U.S. Department of Health and Human Services reports.
Structural problems include fibroid or polyps in the uterus, scar tissue in the uterus from previous surgeries, a misshapen uterus and fallopian tubes damaged by infection, endometriosis or previous surgery.
Male Issues
Male factor issues involve nothing but sperm, but many things can go wrong with them. Male factor issues alone cause infertility in 20 percent of couples with fertility problems, the Mayo Clinic states, and contribute to infertility 30 to 40 percent of the time. Sperm ejaculated today have been in the making for three months, so a prior infection or illness may cause abnormal sperm. A low sperm count, abnormally shaped sperm, and sperm that don't swim well can all cause male infertility. Low levels of male hormones leads to poor or even no sperm production.
Low sperm count can also be caused by varicocele, dilated blood vessels in the testicle, which raise the temperature of the testes, which damages sperm. Congenital chromosomal abnormalities or diseases such as cystic fibrosis also cause male infertility, in some cases. Lifestyle issues such as anabolic steroid use, smoking and strenuous exercise can also reduce sperm counts.
Pregnancy Issues
Sometimes getting pregnant is easy, but carrying a pregnancy may be problematic. Chromosomal abnormalities of the egg or sperm can lead to recurrent miscarriage. Structural problems within the uterus or fallopian tubes can cause miscarriage or pregnancy loss, Advanced Fertility of Chicago explains.
