IVF Drugs are an integral part of over 99% of IVF treatments in the USA, and the stimulation they provide increases the number of eggs that can be collected from a menstrual cycle. The drugs don’t increase the number of eggs in the ovaries for a particular cycle, as each cycle started several months before (eggs and follicles), but stimulation increases the number of eggs that mature. These can be collected at one time which is very different to the single egg that’s usually released from the “dominant” follicle each cycle. However, stimulation isn’t possible when women have:
- High follicle-stimulating hormone (FSH) levels
- Cysts on the ovaries
- Fluid in the pelvic cavity (it increases the risk of infection)
1. Gonadotropin-releasing hormone drugs
The hypothalamus makes Gonadotropin-releasing hormone (GnRH), which controls the menstrual cycle by initiating the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland. These hormones from the pituitary directly stimulate the ovaries to grow eggs and follicles.
Fertility clinics use GnRH drugs to control the timing of cycles, and they’re taken before or alongside other fertility drugs. They’re available as a nasal spray, daily injections, or monthly injections. and there are two classes of GnRH drugs:
- GnRH agonists work by constantly stimulating the pituitary to produce LH and FSH, and they create an initial increase in pituitary activity for ten days, but LH and FSH fall after this. Trade names include Synarel, Suprefact, Lupron and Zoladex.
- GnRH antagonists work by suppressing LH and FSH production from the pituitary, and the advantage of these is there’s an immediate impact on the pituitary function. However, they’re less effective in promoting egg and follicle development than the agonists. Trade names include Ganirelix and Cetrorelix.
The possible side effects of these drugs are hot flushes and night sweats, headaches, mood swings, vaginal dryness, changes in breast size, acne, muscle soreness and osteoporosis with extended use.
2. Follicle-stimulating hormone (FSH)
Follicle-stimulating hormone stimulates the development of many eggs in the ovaries, and there are two sources, which are either synthetically manufactured or refined from human sources:
- Synthetically manufactured FSH. The trade names include Follistim AQ, Cartridge, Gonal-F, Gonal-f RFF and Gonal-f RFF Pen.
- Human refined menotropins (hMG) (“menotrophin” means a fertility-altering substance, and in this case, LH and FSH). The trade names include Menogon, Pergonal, Menopur, and Repronex.
The hormones are collected from the urine of postmenopausal women, and they’re often more effective than synthetic FSH, but they’re also more expensive.
Possible side effects of FSH injections include Ovarian Hyper-Stimulation Syndrome (OHSS), which affects about 2% of women. OHSS is severe and possibly life-threatening and involves a sudden fluid build-up in the stomach or chest area. If the following symptoms are experienced, avoid sex and call a doctor:
- Severe pain in the lower abdomen
- Nausea, vomiting, diarrhoea, bloating
- Feeling short of breath
- Swelling in the hands or legs
- Sudden weight gain
- Urinating less than usual
3. Human chorionic gonadotropin (hCG)
The human placenta produces human chorionic gonadotropin when it implants, and this is the hormone pregnancy tests detect. It’s used in IVF to stimulate the final maturing of the eggs in the follicles. It’s collected from the urine of pregnant women, and the trade name is usually Pregnyl. The possible side effects of hCG include:
- Allergic reactions include hives, breathing difficulties, and swelling of the face, lips, tongue or throat. Stop the hCG and seek emergency medical help if these are experienced.
- Blood clotting is possible, so if pain, warmth, redness, numbness or tingling in an arm or leg, confusion, extreme dizziness, or severe headache are experienced, it’s wise to seek immediate medical help.
- Ovarian hyper-stimulation syndrome (OHSS) is also possible with hCG injections (see FSH medication).
The procedure involves a “scratch” or rubbing of the womb lining with a plastic catheter in the month before a transfer. Changes to the womb lining increase IVF implantation rates by 1.75x, possibly because it instigates inflammation, and implantation is an inflammatory process. The procedure also provides an opportunity for a thorough examination of the uterus before egg transfer, and uterine abnormalities are an issue that affects 28% of patients. ii iii
i SART: Clinic Summary Report, All SART Member Clinics 2010
ii “Impact of luteal phase hysteroscopy and concurrent endometrial biopsy on subsequent IVF cycle outcome” Banu Kumbak, Levent Sahin, Sema Ozkan, Remzi Atilgan. Archives of Gynecology and Obstetrics August 2014, Volume 290, Issue 2, pp 369–374
iii “Outpatient hysteroscopy and subsequent IVF cycle outcome: a systematic review and meta-analysis” Dr Tarek El-Toukhy BioMedicine Online; Vol 16. No 5. 2008 712-719 Reproductive www.rbmonline.com/Article/3207 on web 11 March 2008