Mini-IVF is a procedure that involves ovarian stimulation using low dosage medications (often oral drugs like clomiphene and letrozole) under the premise that it is a “safer” and less expensive than conventional gonadotropin stimulation regimes while yielding comparable success. Nothing could be further from the truth. The fact is that success rates per fresh mini-IVF cycle range between 10% and 12% (i.e., about one third of that which reported national average for conventional IVF performed on  women under 39y of age). And when it comes to older women and those with diminished ovarian reserve (DOR), the success rate with mini-IVF is usually much lower still. There can be little doubt that aside from a woman’s age, the method used for ovarian stimulation represents the most important determinant of egg/embryo quality and  thus of IVF outcome. There is no single stimulation protocol that is suitable for all IVF patients.  It must be individualized…. especially when it comes to women who, regardless of their age have diminished ovarian reserve (DOR) and for women over >40y of age. The reason for this is that in such cases, the pituitary gland often over-produces LH which in turn causes the ovarian stroma/theca (connective tissue) to thicken (stromal hyperplasia/hyperthecosis) and over-produce male hormones (mainly testosterone). This in turn adversely influences egg and follicle growth, resulting in poor egg/embryo “competency” and compromised IVF outcome. So let us examine the validity of the claims made in support of mini-IVF:

1. Milder stimulation using oral agents such as clomiphene, letrozole (alone or in combination with low dosage gonadotropins (Follistim/Gonal-F/Puregon/Menopur) reduces stress on the ovaries and overall risk associated with IVF. This argument while perhaps having some merit when applied to mini-IVF conducted in younger women who also have normal ovarian reserve, does not hold water for older women and those with DOR who (s stated above)  often already have excessive LH-induced ovarian testosterone production. Furthermore, addition of clomiphene and letrozole by  further  increasing pituitary LH (and thus ovarian testosterone) only serves to add “fuel to the fire” in such cases and Menopur which contains both LH and hCG ( that both have similar effects on ovarian testosterone production),  if administered in large amounts (>75U per day) can  also do harm in my opionion. 
2. Women with DOR will respond better to “milder stimulation” and egg quality will so be enhanced. This assertion borders on the ridiculous. It is like saying that applying less force to a heavier object will increase the likelihood of moving it”. That is simply not how FSH stimulates follicle development. You see…the cell membranes that envelop the follicular granulosa cells that line the inside surface of ovarian follicles have on their surfaces, a finite number of FSH receptors. FSH molecules attach to these receptors and mediate intracellular events that lead to granulosa cell proliferation with production of estradiol and the concurrent development of the egg (oogenesis) that is attached to the inner wall of the follicle. Once all the FSH receptors on the cell membranes are saturated, any residual FSH is discarded. This is why, when it comes to older women and women with DOR whose granulose cell membranes harbor fewer FSH receptors, it is virtually impossible to overstimulate them. Excessive FSH will simply be rejected and discarded.
3.  Use of fewer drugs translates into lower cost. This would be true, were it not for the fact that success rates with mini-IVF across the board are much lower than with conventional ovarian stimulation. More important is the fact that the cost of IVF should be expressed in terms of “the cost of having a baby” rather than “cost per cycle of treatment”. When this is taken into account the cost associated with mini-IVF will b be significantly higher than conventional IVF. Then there is the additional emotional cost associated with a much higher IVF failure rate with mini-IVF.
4. Mini-IVF is less technology driven, less stressful and easier to execute. This assertion is in my opinion also without merit. Aside from reduced cost of medications, the same monitoring and laboratory procedures are needed for mini-IVF as with conventional treatment.

What is the best approach? When it comes to older women and those with DOR, it is in my opinion preferable to use a long pituitary down-regulation protocol with conversion from an I.M agonist (e.g. Lupron or Buserelin) to an antagonist such as Cetrotide/Orgalutron or Ganirelix (the agonist/antagonist conversion protocol) augmented with human growth hormone (HGH) and/or estrogen priming and combing this “embryo banking” over several cycles. In such cases preimplantation genetic testing (PGT) can be incorporated to help select the most “competent” embryos for transfer. What about younger women with normal or increased ovarian reserve? If mini-IVF has any role at all, it could be in young women who have normal or increased ovarian reserve.  I do not o not advocate aggressively stimulating the ovaries of younger women who have normal or increased ovarian reserve (as assessed by basal FSH, AMH and estradiol) simply to try and access more eggs. In fact, such an approach is neither safe nor acceptable. In such women it is often wiser to use lower dosage stimulation to try and prevent the development of severe ovarian hyperstimulation syndrome (OHSS) which aside from putting the woman at severe risk of (sometimes) life-endangering complications, can also compromise egg/embryo quality. However, it is my fervent belief that in such women, the preferred approach to ovarian stimulation is through the use of low dosage FSHr-dominant gonadotropins (rather than oral agents such as clomiphene or letrozole and/or high dosage Menopur). This approach is referred to as Micro-IVF.