Lab-grown human eggs may lead to new treatments for infertility.
In a first-of-its-kind study, researchers from the U.S. and the U.K. revealed their success at growing human eggs to a mature state using early-stage ovarian tissue.
The study authors collected ovarian tissue samples from 10 women during elective Cesarean section surgery. The patients donating the tissue were around the same age and at the end of their pregnancies.
The researchers then isolated 48 early-stage eggs from the follicles of ovarian tissue samples. These early-stage eggs were then cultured in a lab, with nine reaching maturity.
While the breakthrough has significant potential, the lab-grown eggs had several abnormalities.
The scientists are undaunted and remain excited for potential future projects to produce quality human eggs. The researchers also hope that this is a first step to developing future treatments for infertility within the next 10 years.
The study is not the first to grow human eggs; previous attempts using human eggs were grown from very late stages of development.
Other attempts to grow eggs have used tissue taken from mice.
Last year, a separate research team grew two types of mouse stem cells in a lab and observed the development of an early-stage embryo grow, which resembled a natural mouse embryo in structure and development but failed to develop into a complete mouse fetus.
The U.S. Centers for Disease Control and Prevention define infertility as the inability to get pregnant after one year or more despite having unprotected sex.
Statistics from the CDC say that 10 to 12 percent of women between the ages of 15 and 44 in the U.S. have difficulty getting or staying pregnant. According to the National Health Service, one in seven women in the U.K. have trouble conceiving.
The World Health Organization has deemed infertility to be a global public health issue. The organization has calculated the global infertility rate to be greater than 10 percent.
"The potential the project has to improve fertility is significant and may replace conventional treatments for fertility, such as in vitro fertilization," said Dr. Mona Alqulali, F.A.C.O.G., Ph.D.
Alqulali is a Bettendorf, Iowa, OB-GYN.
In vitro fertilization, or IVF, is a common treatment for infertility that extracts the eggs from the ovaries and combines them with sperm in a Petri dish. After fertilization, the embryo or embryos are transplanted into the uterus.
"In vitro fertilization can be a difficult, frustrating and emotional process for many couples," Alqulali said.
During IVF, any immature eggs collected during extraction are discarded because at there is no proof that immature eggs can be frozen, thawed and cultured to mature eggs.
Success in future studies could also mean the potential end to needing fertility drugs.
"Fertility drugs frequently have side effects for many women such as headache, mood swings, nausea and hot flashes," Alqulali said.
Other risks of using fertility drugs include a greater chance of conceiving twins, triplets or greater multiples. Women who take fertility drugs are at risk of developing ovarian hyperstimulation syndrome, or OHSS. Women with OHSS produce high numbers of eggs.
"OHSS patients can experience blood clots and kidney failure because of their condition. It can also negatively impact fertility," said Alqulali.
Fertility drugs can also cause the development of ectopic pregnancy, a condition in which the pregnancy develops outside the uterus, usually in the Fallopian tubes. Fertility drugs have also been linked to the development of blood clots, breast cancer, changes in vision and ovarian torsion.
CNN. Human eggs grown in lab offer 'promising' insight into fertility. 2 February 2018.
U.S. Centers for Disease Control and Prevention. FastStats Infertility. 2016.