Antagonist regime provides a more patient-friendly alternative with shorter and more cost-effective ovarian stimulation protocol compared to agonist [4]. It has also been seen that the dropout rates have been much lesser with antagonist cycles than agonist.

GnRH antagonist protocol when compared with long agonist protocol is shorter, rapidly reversible and requires fewer injections and lesser amount of gonadotropins, which definitely makes it more patient friendly and that too at a lower cost. Despite initial studies about the pregnancy outcome being inferior to agonist protocol, more recent studies have indicated that there is not much difference as far as pregnancy rates are concerned and GnRH-antagonist regimen is as effective in preventing a premature rise of LH. Now the flexible dosing regimen is definitely showing promise amongst PCOS [5].

Also GnRH-antagonist protocol becomes a preferred protocol in cases at high risk of developing OHSS and is the protocol of choice for oocyte donation programme because it allows use of agonist trigger for the final maturation, further enabling reduction in OHSS without compromising on the oocyte quality.

Natural cycle IVF is carried out without use of any drugs for ovarian stimulation. The first test tube baby Louise Brown was conceived with natural cycle. But the success rates of IVF dramatically increased only with the use of gonadotropins. Though it provides a cheaper alternative to patients who are ovulating spontaneously and may be indicated in patients with hormone-dependent tumours [6], they need to be counselled regarding the possibility of cancelled oocyte retrieval, fertilization failure and failure to reach embryo transfer [7]. According to HFEA data, only 1/26 cycle in women less than 35 years opting for natural cycle IVF resulted in a live birth in the year 2008.

Minimal or mild stimulation regimes are designed to recruit a fewer number of eggs, thus avoiding the risks of hyperstimulation and reducing the number of injections also dramatically reduce the cost of medications [8]. Frequently low-dose gonadotropins 75–100 IU are used or combined with oral agents like clomiphene with or without use of GnRH antagonist [9]. Sample regime: low dose of clomiphene 50 mg is given without discontinuing the clomiphene after 5 days as is usually the custom but to continue the clomiphene until ultrasound monitoring shows the follicle size ready for ovulation and gonadotropins (150 IU of uFSH) are added on days 8, 10 and 12. Clomiphene not only stimulates the pituitary to release FSH but also blocks the oestrogen-stimulated release of LH so prolonged downregulation with lupride is not required. With this ‘mini- IVF’, though lesser number of oocytes are obtained, less oocyte and embryo aneuploidy is reported and the pregnancy rates are acceptable and similar to conventional protocols.

Mild treatment strategy for in vitro fertilization was shown in a randomized non-inferiority trial by Heijnen et al. [10]to have much lower dropout rates: Mild cycle 5–11 % vs standard cycle 9–19 % and similar cumulative pregnancy with live birth at 1 year: mild: 43 % vs standard: 44 %. In this study, mean total cost of mild IVF was €8,333 while that of a standard IVF protocol was €10,745. Also these regimes drastically lower the multiple pregnancy rates and the associated indirect costs.

Milder stimulation protocols can be used for patients who are presumed high responders, normal responders as well as those with poor ovarian reserve [9] as an option to reduce the cost of stimulation.