Growth Hormone for Poor Responders in in Vitro Fertilization (IVF)

Growth hormone (GH; Saizen®) is indicated for the treatment of growth hormone deficiency in both children and adults, as well as for Turner's Syndrome, chronic renal failure, and children born short for gestational age.

In animal studies, growth hormone has been shown to be important in early antral follicle recruitment, subsequent follicular growth, and oocyte maturation. Together with insulin-like growth factor-1 (IGF-1), growth hormone is essential early on in the recruitment of primordial follicles in the growing pool (Slot et al 2006, Wandji et al 1992, Donadeu & Peterson 2008, Scaramuzi et al 2006, Liu et al, 1998).

Two recent meta-analyses have concluded that the addition of growth hormone during the ovarian stimulation phase of in vitro fertilization (IVF) cycles in poor responders will result in an increased probability of clinical pregnancy (Kolibianakas et al, 2009 and Ahmad et al, 2009). However, these studies have investigated the role of growth hormone in IVF when starting growth hormone injections with the initiation of gonadotropin stimulation. This may be too late to show an effect as GH may have more of an impact in the month prior to stimulation when primordial follicles are in the recruitment phase. Adding growth hormone in the month prior to stimulation with gonadotropins, as well as during stimulation phase may improve IVF outcomes by increasing the number of antral follicles that are recruited in the month prior to a stimulated cycle, and may ultimately improve the response to gonadotropin stimulation.

Starting growth hormone prior to stimulation has been studied in one previous publication (Kucuk et al, 2008), and showed that by starting growth hormone on day 21 of the menstrual cycle preceding gonadotropin stimulation, and continuing co-treatment with growth hormone until human chorionic gonadotropin (hCG) trigger resulted in a significantly higher number of fertilized oocytes when compared to a control group receiving no growth hormone (4.4 +/-1.8 vs 1.5 +/-0.9; p<0.001).

The addition of growth hormone to an IVF treatment protocol is directed at those infertile women who have previously undergone an IVF cycle on maximal doses of gonadotropins with a poor ovarian response. This study is aimed at improving IVF success in this population of women at the Ottawa Fertility Centre.

The purpose of this study is to determine if the addition of growth hormone both in the month prior to gonadotropin stimulation and during the active phase of stimulation, will result in an increased number of mature oocytes retrieved in previously poor responders during an IVF cycle.

Inclusion criteria

• less than 42 years of age
• previous IVF cycle with high doses of gonadotropins (defined as greater than or equal to 400 IU/day)
• produced less than 6 follicles greater than or equal to 15mm

Exclusion criteria

• any known contraindications to the approved fertility drugs as per the Canadian Product Monographs
• any contraindications to growth hormone, pregnancy (to be ruled out and documented before GH treatment), or are at risk for gestational diabetes