Concordance of Fingerstick and Venipuncture Sampling for Fertility Hormones

[helvella]

A frequently asked question here is whether home-draw blood tests using lancets to obtain small amounts of blood are comparable to the standard large samples taken from our veins.

Whilst we have had quite a number of people report that when they had two tests done very close in time, the results were almost always just about perfectly in agreement, it is good to see a paper specifically investigating this.

Shame the number involved wasn't much, much greater.

Obstet Gynecol. 2019 Jan 8. doi: 10.1097/AOG.0000000000003066. [Epub ahead of print]

Concordance of Fingerstick and Venipuncture Sampling for Fertility Hormones.

Burke EE1, Beqaj S, Douglas NC, Luo R.

Author information

Abstract

BACKGROUND:

Minimally invasive fingerstick sampling allows testing of reproductive hormone levels at home, providing women with increased access to tests that can screen for conditions such as polycystic ovarian syndrome, primary ovarian insufficiency, and pituitary and thyroid dysfunction.

METHOD:

We present a measurement procedure comparison study of matched venipuncture and fingerstick samples from 130 women aged 18-40 years, tested on menstrual cycle day 3. Samples were measured for anti-müllerian hormone, estradiol (E2), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), testosterone, thyroid-stimulating hormone (TSH), and free thyroxine (T4) levels. Samples were tested using U.S. Food and Drug Administration-cleared immunoassays, with a modified reconstitution step for fingerstick samples.

EXPERIENCE:

Venipuncture and fingerstick hormone values were concordant and linear across all assay ranges. There was no evidence of systematic bias across the assay ranges, and bias measures were below recommended guidelines. The correlation between venipuncture and fingerstick was between 0.99 and 1.0 for each hormone. Each assay displayed a high degree of precision (less than 13% coefficient of variation) and a high level of accuracy (average recovery equaled 95.5-102.3%).

CONCLUSION:

Venipuncture and fingerstick samples can be used interchangeably to measure anti-müllerian hormone, E2, FSH, LH, PRL, testosterone, TSH, and free T4 levels. Fingerstick sampling provides doctors and women more convenient testing options.

FUNDING SOURCE:

The study was sponsored by Modern Fertility.

PMID: 30633131

DOI: 10.1097/AOG.0000000000003066

ncbi.nlm.nih.gov/pubmed/306...

SeasideSusie

LV2475

[SeasideSusie Remembering]

Excellent Helvella, many thanks. A great post to bookmark and refer to in reply when the question comes up in future.

[jimh111]

It does seem that fingerprick tests are accurate provided care is taken. I haven't read this study but beware it was sponsored by a company that supplies fingerprint tests! Reports from patients who have run both tests at the same (ish) time are more reliable.

[helvella Administrator Thyroid UK in reply to jimh111]

I agree that we should be wary.

[MaisieGray in reply to jimh111]

Surely that is faulty logic, and at best an assumption? That the result of A's activity might be faulty, because of reason X, doesn't necessarily mean that the result of B's activity in the absence of reason X will de facto, be more reliable. There could be other factors that make B's result less or as unreliable; or A may be wholly truthful..

[jimh111 in reply to MaisieGray]

I'm only raising an issue of potential bias. Research may have flaws but when there is a commercial interest the research can be intentially biased. e.g. Companies can carry out multiple tests in secrete and then carry out a formal trial with the test design that gives the 'best' result. In the case of fingerprick tests it's theoretically possible to get good results with expert technique which may not reflected in general use.

In the case of fingerprick TFTs they do seem to give accurate results but we should still be on the lookout for potential bias when studies are published by vested interests. Tobacco manufacturers knew for decades that their product was lethal but chose to withold this information.